1. Field of the Invention
The present invention relates to a structure of a seat cushion frame in an automotive seat, and is particularly directed to that kind of structure wherein the seat cushion frame is variable its length in the fore-and-aft direction of the seat, without requiring replacement of the frame per se by another one.
2. Description of Prior Art
In the past, an ordinary seat cushion frame, which is provided within a seat cushion of an automotive seat, has been formed by bending a tubular material into an rectangular shape, with a sinuous springs being extended between both lateral bar sections of the frame, or by subjecting a metallic plate to a press working process so as to obtain a desired pan-type frame. Since this sort of frame can never be varied its length in the fore-and-aft direction of the seat, and to create different of seat cushion frames with different fore-and-aft lengths, there has been a need to form individual frames to meet such different length geometries, resulting in troublesome labor for preparing different frames for corresponding different seat cushion frames.
As a possible solution to this problem, such a frame structure is proposed, that comprises a forward frame, a rearward frame and a pair of lateral side frames, such that all the frames are provided separately, and the forward and rearward frame are of the same frame material with the same dimensions for permitting a common use of them. According thereto, varying the length of both lateral side frames may meet the foregoing demand for producing seat cushion frames with different fore-and-aft lengths. However, this particular structure is found defective in requiring extraordinary steps of assemblage and mandate involved.